#define RED_PIN 3    // Assuming pin 3 for the red color

int main() {
  pinMode(RED_PIN, OUTPUT);

  int brightness = 0;  // Starting brightness

  while (true) {
    // Red to off transition
    for (brightness = 255; brightness >= 0; brightness--) {
      analogWrite(RED_PIN, brightness);
      delay(10);  // Adjust this delay for speed control
    }

    // Off to red transition
    for (brightness = 0; brightness <= 255; brightness++) {
      analogWrite(RED_PIN, brightness);
      delay(10);  // Adjust this delay for speed control
    }
  }

  return 0;
}